(1) Field of the Invention
The present invention relates to processes for power plants and the chemistry of inorganic compounds. The invention particularly relates to such processes involving the addition of water and oxidizers other than air to provide useful power and pressurized fluid. The invention also relates to reaction processes where the product includes elemental hydrogen from decomposition of a hydrocarbon or water and where the reaction includes a metal or metallic compound.
(2) Description of the Related Art
Liquid oxidizers used for propellants typically include hydrogen peroxide, inhibited red fuming nitric acid, nitrogen tetroxide, and liquid oxygen. These oxidizers have various deficiencies including corrosivity, high initial cost, short storage life, high disposal cost, and dangerous properties such as being hypergolic. Other deficiencies include toxicity and environmental danger from both the oxidizer and its reaction products.
To avoid these deficiencies, it is known to react water and aluminum powder to provide reaction products, including hydrogen, for rocket propulsion, particularly rocket torpedo propulsion. However, arrangements using this reaction have suffered from high combustion temperatures, erosion, slaging, and problems with metering dry solids into the combustor.
As shown by the following United States Patents, the reduction of water or a hydrocarbon with a metal containing material to generate hydrogen is known, as is the use of water with the combustion of hydrocarbons in power producing devices.
U.S. Pat. No. 5,012,719, which issued 7 May 1991, discloses the generation of hydrogen for projectile propulsion from a barrel by “exothermically reacting water or a water-hydrogen peroxide liquid mixture with metal or a metal hydride”, the reaction being controlled by the power provided to a plasma source from which a plasma jet is propagated into a reaction chamber containing the reaction materials. This chamber contains a honeycomb structure having different compartments filled with particles of the metal or metal hydride, water, and air in “amounts proportional to the mole fractions of the reactants in the exothermic reaction”. The metals aluminum, zirconium, titanium, silicon and their hydrides are stated to be suitable. The honeycomb structure may itself be the metal or metal hydride, but may also be “fabricated of a hydrocarbon, dielectric material, such as polyethylene”. It is apparent that this patent discloses a “one-shot” reaction and the use of only a small quantity of hydrocarbon which is solid and only forms a container structure. Further, this patent states: “The energy in the gas generated . . . may be 1.5 times the electric energy coupled . . . to [the] plasma source because of the additional exothermic reaction energy.” It is apparent that the arrangement of U.S. Pat. No. 5,012,719 produces little more energy, or even less energy, than is required for its operation and is directed at controlling the hydrogen producing reaction for projectile propulsion rather than the production of other mechanical work or hydrogen.
U.S. Pat. No. 3,932,600 issued 13 Jan. 1976 and discloses a process for the generation of hydrogen wherein “particles of magnesium are reacted with water in the presence of at least one cobalt oxide and at least one water-soluble chloride”. Aluminum may be included with the magnesium, and seawater may be used to provide the chloride. However, no hydrocarbon is utilized.
U.S. Pat. No. 3,955,941 issued 11 May 1976 and discloses a representative process for reforming hydrocarbons into hydrogen without the use of a metal as a reactant or as a catalyst. First, air and hydrocarbon fuel are ignited to “provide hot combustion gases, by partial oxidation of the hydrocarbon fuel”. In a separate region, water is then injected “whereby a steam reforming reaction with the hydrocarbon fuel takes place to produce a hydrogen rich gas.”
U.S. Pat. No. 3,985,866 issued 12 Oct. 1976, and discloses a method of producing high pressure, hydrogen containing gas for use as a power source by bringing a metal fuel in the form of molten droplets into contact with water. The fuel has aluminum as a primary component plus at least one of lithium, magnesium, sodium, or potassium in the form of an alloy or a mixture. For a mixture, the fuel is provided as a slurry having the auxiliary fuel component as the liquid phase, and the slurry is injected into an atmosphere containing water vapor. Seawater may be used, but no hydrocarbon is mentioned.
U.S. Pat. No. 3,986,909 issued 19 Oct. 1976 and discloses propellant compositions containing finely-divided boron present in excess of the amount oxidizable during combustion of the propellant so that the boron is ejected with the combustion products for burning in an afterburner combustion zone. The propellant includes an organic polymer binder and an inorganic oxidizer salt, and may “contain small amounts of Mg, Al, or Zr metal as ballistic or afterburner combustion modifiers.” However, no water or hydrocarbon is utilized.
U.S. Pat. No. 5,329,758 issued 19 Jul. 1994 and discloses a steam-augmented gas turbine in which water is provided to a combustor along with fuel and compressed air. However, no metal is involved in the reaction, and the water does not take part in the combustion chemical reaction, but only increases the mass flow.
U.S. Pat. No. 5,803,022 issued 8 Sep. 1998 and discloses a reciprocating engine in which water is injected into a combustion chamber into which a fuel injector provides fuel-rich combustion gases ahead of steam from a water injector. The water injector may incorporate phase-change of the water by electrical heat and electrolytic dissociation of the water into hydrogen and oxygen. However, no metal containing substance is used in the power producing reaction.
U.S. Pat. No. 6,103,143 issued 15 Aug. 2000 and discloses a representative cyclic process for “steam reforming of hydrocarbon, particularly methane, under elevated temperature and pressure to produce hydrogen”. Steam and hydrocarbon are “fed into a first reaction volume containing essentially only reforming catalyst to partially reform the feed.” The reaction products, carbon dioxide and hydrogen, and additional feed are provided into “a second reaction volume containing a mixture of catalyst and adsorbent which removes the carbon dioxide”. These reactions are followed by depressurization of the reaction volumes, purge of the adsorbent, and repressurization. Any well-known steam-methane reforming catalyst may be used, examples including nickel-alumina, nickel-magnesium alumina and the noble metal catalysts; however, no metal or oxidizer is used in the reaction itself.